ABSTRACT
It is not the purpose of this chapter to enter into a discussion of the development and use of analytical and computer models as such. The reader should consult the many available textbooks that deal directly with development of analytical computer models. The material presented in this chapter is meant to provide an overview of the modelling requirements and challenges as they relate to (a) clay barrier/buffer used in engineered multi-barrier systems for isolation of high-level radioactive wastes (HLWs) in repositories and hazardous solid wastes (HSW) in landfills, and (b) a summary account of some of the models used to address the repository and landfill situations. In the design of engineered barrier systems (EBSs) for deep geological repository containment of HLWs and secure landfills for HSWs, modelling of the integrated performance of all the involved components is required.
